This invention relates to a multipoise furnace and, specifically, to a hinged front access door and a safety shutoff switch within a multipoise furnace.
The term multipoise furnace, as herein used, refers to a furnace that can be positioned on either its bottom, top, left side or right side such that the furnace may discharge air in either an upward or downward direction, as well as horizontally to the left or to the right. While most furnaces that may be installed in different positions require extensive modifications when changing orientation, the ability to selectively position a the multipoise furnace exists without modification.
A multipoise furnace includes a blower that draws return air from a comfort zone into a blower housing and forces the air throughout the furnace. Access into the blower housing typically has been achieved by providing an access door that is permanently attached to the furnace. Such an access door, however, may restrict complete access to the blower and complicate assembly of the furnace.
Also associated with the blower housing is the safety shutoff switch. Upon opening the access door, the shutoff switch terminates power to the furnace's control center, causing all components to become temporarily inoperative. If the switch fails to render the blower inoperative, maintenance becomes dangerous as the technician is exposed to an operating blower and its power supply. Furthermore, if the switch fails or does not terminate power immediately upon opening the access door, inefficient operation and early deterioration of the furnace results as unfiltered air enters and deposits throughout the furnace. Failure of the shutoff switch to properly terminate blower operation, however, exists as a probable result when placement of the switch within the housing exposes it to grease, dirt, and the possibility of accidental activation when working within the housing.